The term "television receiver" as used herein includes television receivers having a display device (commonly known as television sets), and television receivers without a display device, such as videocassette recorders (VCR's).
The term "television receiver" as used herein also includes television monitor/receivers having an RF tuner and baseband signal input circuitry.
Many modern television receivers have picture-in-picture (PIP, or PIX-IN-PIX) capability, that is, the capability to receive video signals from two sources and combine them to produce a signal which when displayed includes a first program in a main viewing area, and a second program in a secondary (inset) viewing area of the same display screen.
In addition to displaying an inset picture in one of the corners of the display, modern PIP circuitry also provides for the horizontal and vertical movement of the inset image about the display screen. Horizontal movement of the inset image is called "panning". Vertical movement of the inset image is called "scrolling". A system having this capability is known from TOSHIBA television receiver model 30ID1. Unfortunately, the TOSHIBA system produces horizontal and vertical motion of the inset image about the display screen that is noticeably and undesirably erratic (i.e., jerky).